Physical Chemistry Questions

15 pts For the reaction N g 3H 2NH3 g the equilibrium constant is Kp 1 245 at 400 K A mixture have the following compositions at 400 K and a total pressure of 1 00 bar 0 0983 mol N2 g 0 136 mol H g and 0 0706 mol NH3 g Suppose that 0 100 mol N2 g is added at constant pressure to this mixture What will be the partial pressure of H2 g after equilibrium is established in this mixture a b C d 0 7149 atm 0 7373 atm 0 1520 atm 0 3697 atm X

The freezing point depression of a 0 1 M aq solution of weak acid HX is 0 20 C What is the value of equilibrium constant for the reaction HX aq H aq X aq Given K for water 1 8 kg mol K Molality Molarity A 1 46x10 C 1 21x10 B 1 35x10 D 1 35 10

The enthalpy of dissolution of BaCl2 s and BaCl2 2H O s 1 are 20 6 and 8 8 kJ mol respectively The enthalpy of hydration for BaCl2 s 2H O BaCl 27 A 45 8 kJ B 29 4kJ C 11 8 kJ D 38 2 kJ

enzene is 35 The entropy of vaporization or 85 JK mol When 117 g benzene vaporizes at its normal boiling point the entropy change of surrounding is 85 J K 3 85 x 1 55 J K 2 85 x 1 5 J K 4 None of these

Passage of three faraday of charge through aqueous solution of AgNO3 CuSO4 Al NO3 3 and NaCl will deposit metals at the cathode in the molar ratio of b 6 3 2 6 d 3 2 1 0 a 1 2 3 1 16 3 0 0 the following h

3 When an electron de excites from higher orbit in H atom two radiations are emitted out in Paschen and Lyman series The wavelength of radiation emitted out in Lyman series is a BR 9 b 3R 4 4 C 3R 9 d BR

The enthalpy of neutralization of HCI and NaOH is 57 kJ mol The heat evolved at constant pressure in kJ when 0 5 mole of H SO4 react with 0 75 mole of NaOH is equal to B 57x0 5 D 57x0 25 3 A 57x 4 C 57 SPACE FOR ROUGH WORK

All Physics View in Question No 13 At 100 K temperature Az g is 50 dissociated into B g and C g as per the reaction A2 g B g C g at 1 atm pressure The Gibbs energy change at this temperature is 0 100 Rin3 O 100 Rin3 O 230 3 Rin3 O230 3 Rin3

In the electrolysis of AgNO3 the mass of Ag deposited is plotted against the charge mass of Ag deposited slope of line tan 0 0 Q Charge Slope of the line gives 1 Equivalent mass of silver 2 Electrochemical equivalent of silver 3 value of faraday 4 Current passed through the cell

Question Type Single Correct Type 1 Hydrolysis of XeF2 is redox process 2 PCI5 on complete hydrolysis yield H3 PO4 3 On Hydrolysis of XeF4 Xe XeO3 are obtained as products 4 On hydrolysis of H3PO3 H3PO4 PH3 are toined

Hydrolysis constants of two salts K and hA KB of weak acids HA and HB are 10 8 and hB 10 6 If the dissociation constant of third acid HC is 10 2 The order of acidic strength of three acids will be A HA HB HC B HB HA HC CHC HA HB D Correct Answer HA HB HC

2 14 Two tiny spheres carrying charges 15 C and 2 5 C are located 30 cm apart Find the potential and electric field a at he midpoint of the line joining the two charges and b at a point 10 cm from this midpoint in a plane normal to the line and assing through the midpoint

D CH NH 0 1 mole K 5 x 10 4 is added to 0 08 moles of HCl and the solution is diluted to one litre The resulting hydrogen ion concentration is 1 1 6 x 10 11 3 5 x 10 5 2 8 x 10 11 4 8 10

What will be he pressure of the gase mixture at equilibrium if AB is 20 dissoci according to the following react AB g A g 2B g Kp represents equilibrium constant of the reaction

What is the proportion mole ratio of benzoic acid a monoacid chain capping agent that should be used with an equimolar mixture of adip acid and hexamethylene diamine to produce a polymer of 10 000 g mol at 99 5 conversion Again you can neglect end groups Select one O a 0 978 O b 0 944 OC 0 0186 O d 0 022 e 0 056

Select the incorrect option among the following e m ratio of proton is 1 758820 x 10 1 C g e m values of anode rays generated by discharge of different gases are different Millikan s oil drop experiment was used to calculate the charge on electron e m ratio of electron was determined by J J Thomson

Which one of the following characteristics is associated with adsorption Question Type Single Correct Type 1 AG is negative but AH and AS are positive 2 AG AH and AS all are negative 3 A AG and AH are negative but AS is positive AG and AS are negative but AH is positive

R n 2 n 2 4n 4n d 1 mole of atom The energy emitted when electron of 1 09 atom of hydrogen undergoes transition giving the spectral lines of lowest energy in the visible region of its atomic spectra is a 301 22 kJ b 328 kJ c 984 kJ d 182 22 kJ ories of lines in the spectrum of atomic hydrogen lines at wavelength 656 46 486 27 434 17 410 29 m

A layer of 0 25 mm thick chromium metal is to be electroplated on the rims of autovehicle with a total area of 32 m from a solution of Cro What amount of electric current is required for electroplating the rims in 60 sec The density of chromium metal is 7 2 g cc A 4 9 10 A B 1 78 10 A 5 3 10 A D 10 69 x 106 A

A sample of 10 mol gas expands isothermally reversibly to double its volume from 1 L to 2 L The AU for the process is 00 O 20 L atm O 20 Latm O 10 Latm

Q 1 Tick mark the correct answer 1 The ratio of the sine of the angle of incidence to that of refraction is constant and it is the characteristic of a liquid This is a Lorenz s law d Maxwell law 2 Molar refraction has unit b Snell s law c Debye law

If 1 mol of HA weak monobasic acid is neutralised by 1 mol of NaOH and total heat released is used to raise temperature of 7 mol of ice from 10 C to 10 C If heat of neutralisation of 1 mole of strong acid with 1 mole of strong base is 57 057 kJ heat of ionisation of HA in kJ mol is Afusion of ice 6 03 kJ mol 1 Cp H 0 1 75 3 J mol K 1 Cp H 0 s 36 8 J mol K 1

Which of the following is not a colligative property Relative lowering of vapour pressure Elevation in the boiling point Freezing point Osmotic pressure

d Mg is precipitated 0 Normal Al AlCl3 coupled with normal hydrogen electrode gives an e m f of 1 66 V The standard oxidation electrode potential of aluminium is a 1 66 V b 1 66 V E Ea c 0 83 V d 0 83 V many faraday are needed to reduce a molec 4x2 1

1 g 2XO g X g 20 g K K K 1 x 1024 K 2 5 x 1010 So the stability of XO XO BEGINNER S BOX 2 In which of the following reaction product is more stable 1 N 3H 2NH K 2 3 10 2 N O 2NO K 2 10 x 3 H 1 2HI K 294 4 XeO O F XeO F K 1 4 10 F2 2 KA

A reaction in equilibrium in a 1 00L container is found to contain 0 025 moles of A 0 097 moles of B and 0 118 moles of C A B C Calculate the value of Kc for the reaction If 0 067 moles of A and 0 082 moles of B are added to the reaction how many moles of C will be present at equilibrium

base indicator has Kin The acid form of the indicator is red and the 3 0 x 10 5 basic form is blue The change in H required to change the indicator from 75 red to 75 blue is 1 8 x 10 5 M 3 3 10 5 M 2 9 x 10 5 M 4 3 x 104 M 195 W C

Match incorrect equivalent mass of reactant in following column M molar mass of reactant Column I 1 FeS Fe SO 2 P H P H PH 3 2Mn7 Mn Mn 6 4 Ba MnO H Mn Column II M 15 5M 6 M 3 M 5

5 00 mL of 0 10 M oxalic acid solution taken in a conical flask is titrated against NaOH froma burette using phenolphthalein indicator The volume of NaOH required for the appearance of permanent faint pink color is tabulated below for five experiments What is the concentration in molarity of the NaOH solution Exp No 1 2 3 4 5 Vol of NaOH mL 12 5 10 5 9 0 9 0 9 0

Which of the following is incorrect about NaCl structure A Nearest neigbours of Na ion is six Cl ion B Na ion make fcc lattice C CI ion pack in cubic close packed arrangement D There are eight next nearest neighbours of Nation

For which of the following acid base pair enthalpy of neutralisation is 13 7 kcal CH3COOH NaOH CH3COOH NH4OH NH4OH HCI NaOH HCI

The standard emf of the cell Pt s H g HBr aq AgBr s Ag s was measured over a range of temperatures and the data were fitted to the following polynomial E V 0 07131 4 99 10 T K 298 3 45 10 T K 298 Evaluate the standard reaction Gibbs energy enthalpy and entropy at 298 K

The boiling point of C6H6 CH3OH C6H5NH and C6H5NO are 80 C 65 C 184 C and 212 C respectively Which will show highest vapour pressure at room temperature 1 C6H6 2 H NH 2 CH OH 4 CH NO

Which of the following reaction is endothermic reaction 1 Bond formation by two unstable atoms at certain condition 2 Combustion reactions 3 Conversion of more stable allotrope to less stable allotropic element 4 Condensation of vapour to its liquid state

Answer B Your Attempt A a b are constants for a gas at any temperature and pressure Correct answer D a b are not strictly constants and vary with temperature and pressure C The values of a b are same according to different equations for real gases For real gases TB where To is the Boyle s temperature Rb Rate

An aqueous solution contains 0 26 M ammonium nitrate One liter of this solution could be converted into a buffer by the addition of Assume that the volume remains constant as each substance is added 0 25 mol NH3 0 06 mol Ba OH 0 26 mol HCIO4 0 12 mol HC104 10 25 mol Ca NO3 2

1 A 5 5 L balloon is completely filled with air indoors at a temperature of 21 0 C The balloon is taken out on a cold winter day If the final volume of the balloon is 4 5 L what is the final temperature in Celsius 3 marks

0 1 M glucose Which of the following solution will exhibit highest boiling point 0 1 M NaCl 0 1 M CaCl TK TOT Review 0 1 M AICI 3 hr m

reaction N g 3H g under certain conditions of temperature and partial pressure of the reactants the rate of formation of NH is 0 001 kg lit h The rate of conversion of H under the same condition is kg lit h 1 0 001 kg lit h 2 0 0015 kg lit h 1 3 0 00017 kg lit h 4 0 0017 kg lit h 1

Which of the following is incorrect regarding Gibbs energy Question Type Single Correct Type 1 It is a state function 2 It is a macroscopic property 3 Change in Gibbs energy decide spontaneity of a process A It is intensive property

a c 439 3 Considering thermodynamic entropy S as parameter the criterion for the spontaneity of any process is a ASsystem AS surroundings 0 b AS system AS surroundings 0 c AS system 0 only d AS surroundings 0 only 200 the expansion

For which of the following reaction AH AU PCI5 g PCl3 g Cl g CO g H O g CO g H g CaCO3 s CaO s CO g N g 3H g 2NH3 g

On dissolving sugar in water at room temperature solution feels cool to touch Under which of the following cases dissolution of sugar will be most rapid A Sugar crystals in cold water B Sugar crystals in hot water C Powdered sugar in cold water D Powdered sugar in hot water Medium The web pages from your last visit have not Feedback

According to third law of thermodynamics which property of any pure crystalline substances approaches zero as the temperature approaches absolute zero U H

15 Standard enthalpy and standard entropy changes for the oxidation of ammonia at 298 K are 382 64 kJ mol and 145 6 kJ mol respectively Standard Gibbs energy change for the same reaction at 298 K is a 221 1 kJ mol b 339 3 kJ mol c 439 3 kJ mol d 523 2 kJ mol

3 a 8 25 g cm c 42 5 g cm 3 MCS d 0 425 30 If NaCl is dopped with 10 mole of SrCl2 concentration of cation vacancies will be the a 6 02 x10 6 mol 1 c 6 02 x10 4 mol 1 AIPMT 2007 b 6 02 x10 mol 1 d 6 02 10 5 mol 1 JAIPMT 2007 ion of total volume occupied by the atoms

The mass of urea that would be dissolved in 180 g of water in order to produce the same lowering of vapour pressure a is produced by dissolving 19 g of cane sugar C12H22011 in 100 g of water is 10 g 5 g 3 5 g hr min 6 g

The total number of unit cells present in 80 g of X that crystallises in fcc unit cell is Atomic mass of X is 40 u N 0 2 N 8 N Mark for Review 2 NA

If for a reaction in which A g converts to B g the reaction carried out at const V T results into the following graph PB A Time 1 then the reaction must be A g 3B g and is a first order reaction Partial Pressure O PA 2 then the reaction must be A g 3B g and is a second order reaction 3 then the reaction must be A g 3B g and is a zero order reaction 4 then the reaction must be A g 3B g and is a first order reaction

If NaCl is doped with 10 1 mol of SrCl the concentratio of cation vacancies will be 6 02 x 1022 6 02 1020 6 02 x 1023 hr mir 6 02 x 1018